1. Field of the Invention
This invention relates to a hook-and-loop fastener otherwise known as a surface fastener comprising two layers of fabric which are releasably engageable with each other. One of the fabric layers carries hook-shaped or male elements engageable with loop or female elements on the other fabric layer. The present invention is more specifically concerned with a warp-knit support tape for such hook-and-loop fasteners carrying thereon a multiplicity of pile-loop elements and engageable with a mating hook-carrying tape.
2. Description of the Related Art
There have been proposed many different forms of hook-and-loop fastener tapes, one such tape being disclosed in Japanese Utility Model Application No. 60-162742 (corresponding to U. S. Pat. No. 4,709,567 issued Dec. 1, 1987) to which the present invention is interrelated. The disclosed hook-and-loop fastener tape, as shown in FIG. 4 of the accompanying drawings, comprises a foundation web consisting two-needle stitches and laid-in weft threads, and a multiplicity of pile loops, in which the sinker loops of the two needle stitches are arranged to urge and hold the leg portions of the pile loops criss-cross against the foundation web, while the laid-in weft threads fill up in between the sinker loops and the pile loops, thus anchoring the pile loops stably in place against displacement or dislocation. The sinker loops of the two-needle stitches and the laid-in weft threads are further arranged to bear against the foundation loops which form the wales, so that the fastener tape as a whole is rendered highly resistant to stretch in either direction.
While the above-mentioned prior art device is satisfactory in its resistance to displacement or dislocation of the piles, it has been found somewhat defective in the ability of engaging with hook elements on the mating counterpart on account of the fact that the pile loops alternating on the right and the left side of the wales are prone to tilt down flat on the tape surface in opposite directions.